Soil and land resources of Morogoro urban district, Tanzania

A semi-detailed characterization of soils ofMorogoro Urban district was carried out to provide a physical resource base for developing suitable programmes on land use planning, agricultural development and natural resources conservation at district level. The generated information would also be used for develop the agricultural land suitability, with a statement of potential and constraints on sustained use of soil and land resources of Morogoro Urban district. Results of the study could also facilitate transfer of agrotechnology from one area to another. Base map for the study was compiled from aerial-photo interpretation and subsequent overlaying on 1:50,000 scale topographic map of the district. A geological map was later on prepared and overlain on the former map to produce a landform and geology map of the district. A tentative working legend based on landforms and geology was developed for the landform and geology map. Field observations on soil morphology and their spatial distribution were carried out following the established landform and geology units. Soils were studied and described according to standard FAO (1990) guidelines. Both disturbed and undisturbed soil horizon samples were taken for laboratory studies including physico-chemical and mineralogical characterization of the soils.Sokoine University of Agricultur

Factors influencing soil distribution and their implication for agricultural land management in Morogoro urban District, Tanzania

Proceedings of tbe 1st University Wide Scientific Conference, 2000; Vol 2:161 - 171A standard soil and land resources survey was conducted in Morogoro Urban District, Tanzania to investigate the factors influencing characteristics and spatial distribution of soils and their implication for land management. Landforms, parent materials, climate, soil morphological, physicochemical and mineralogical properties were the main attributes studied. Soils were classified according to the FAO-World Reference Basefor Soil Resources. Six major landforms were identified namely; strongly dissected mountain ridges, mountain foothills, hills, piedmonts, peneplains and valleys. The strongly dissected mountain ridges comprise complex soils developed on pyroxene granulites. The soils include shallow, excessively drained sandy clay loams and deep well drained sandy clays and clays. The soils were classified as Lithic-Paralithic Leptosols, Hapli-Profondic Lixisols, Orthidystri-Episkeletic Cambisols and Hypereutri-Episkeletic Cambisols (Haplic). The hills are a complex of rock outcrops and shallow soils developed on muscovite-biotite migmatites. The soils are excessively drained, extremely gravely sandy loams and sandy clay loams. The soils were classified as Lithic Leptosols. The piedmonts and peneplains comprise largely associations of deep and very deep, well drained clays and sandy clays. These soils developed on colluvium derived from granulites and migmatites were classified as Chromi-Profondic Acrisols, Chromi-Profondic Lixisols, Rhodi-Profondic Luvisols and Cutani-Profondic Luvisols (Haplic). In the valleys, the soils are developed on alluvium of diverse mineralogical composition and are a complex of Calcari- and Stagni-Mollic Fluvisols and Calcari-Salic Vertisols. All the studied soils except those of the valleys have low soil fertility as shown by low organic carbon «1.0%), low levels of major nutrients (nitrogen <0.1%, phosphorus <5 mg/kg) and low CEC «12.0 cmol(+)lkg soil). Although the soils of the valleys are fertile, they are characterised by one or more of the following problems: poor drainage condition, high alkalinity and salinity (ESP >5%) and difficult workability. The results of this study show a close relationship between landforms, parent materials and soil types. The paper establishes some land qualities which are important for sustainable agricultural land management in the district